Background: The length of maternal hospitalization in uncomplicated delivery has declined and it has become common event around the world. With the expansion of early maternal discharge from hospital in recent years, the identification, follow-up and proper treatment of neonatal problems such as jaundice have been confronted with challenges. Hyperbilirubinemia is the most common disease among neonates especially preterm neonates during the first week of life. This study was performed aiming to investigate maternal hospitalization duration after delivery and its effect on neonatal jaundice level.Methods: In this descriptive-analytical study, 1347 newborns with the jaundice hospitalized in neonatal clinic or emergency unit or neonatal intensive units of Ghaem Hospital, Mashhad, during May 2011 to November 2017 were investigated. The data collection tool was a researcher-made questionnaire containing three parts. First part was maternal demographic information (age, long hospitalization, and mode of delivery), Second part was neonatal information (serum bilirubin, hematocrit and platelet) and third part was laboratory information (serum bilirubin, hematocrit, and platelet). The relationship between the severity of jaundice in hospitalized infants and maternal hospitalization duration were evaluated. Values were expressed as mean±SD. Student t-test, chi-square and Pearson coefficient tests were used as appropriate. P-value less than 0.05 was considered significant.Results: 752 (fifty six percent) of mothers are discharged from the hospital at the end of first day. The mean maternal hospitalization duration was 1.31±0.57 days in normal delivery and 1.73±0.65 days in cesarean delivery (P=0.000). Pearson correlation test showed that increasing the duration of maternal hospitalization, some issues were observed including as decreasing serum bilirubin level (P=0.000) in newborns, increasing the admission age in hospital (P=0.045), decreasing daily weight loss rate (P=0.012) and decreasing the percentage of daily weight loss (P=0.002).Conclusion: By increasing the hospitalization duration of the mother in hospital, serum bilirubin level, rate and percentage of daily weight loss in the newborns would be decreased.